I think it would be fair to say that based on the current makeup of the RNoN fleet, that while a 'Type-26' would be an ideal vessel to acquire, the cost is 'limiting'. An alternate maybe to 'buy' into the manufacturing line, have a Type-26 Hull form produced, but don't fit ALL the same kit.
I know that may sound counter-intuitive, but hear me out...
If the design is 100% identical, it costs more.
By taking some systems / equipment out / removing compartments / having systems as 'IPMD / FFBNW', it reduces the costs, the installation / fit-out / testing time & allows RNoN to fit the equipment at a later date, or actually not fit the kit at all & use the space for something else at a later date.
NEED Hull form / need the engines / gearbox / radar / command system, but DON'T fit the Missiles / CIWS / the 5 inch gun / pull thru kit from elsewhere in the fleet / Get a smaller gun (like 76mm from Leonardo) &u REDUCE overall purchase costs.
HOWEVER - do as Australia has done & change / make different from the UK Baseline design & you costs will be MORE than a baseline ship from UK.
SA
I agree that if you look at the current makeup of the RNoN fleet your proposals would make a lot of sense.
However, two things to keep in mind:
1. The current fleet was built when Russia was basically no threat, it was still recovering after the crash of the USSR, and Norway like most other European countries were slashing defence budgets right and left ("peace dividend"). Now the situation has changed dramatically. Russia has demonstrated extreme aggressiveness. and clearly want to rebuild it's empire. In addition, the US is gradually shifting focus to China, which implies less focus on Europe and potentially less military support available in the future. Norwegian analysts are very clear: Norwegian Navy in it's current state is close to useless, and must be rebuilt.
2. Norway is disgustingly rich. We have the "oil fund" which seems to just keep growing and growing. The politicians has decided that any year they should not spend more than 3% of the oil fund (some years ago the limit was 4%). If there is an emergency they could theoretically declare an emergency and use even more. Thus, unlike almost all other countries on this planet Norway can increase defence budget significantly without worrying about increasing taxes or borrowing money. A couple of years ago defence was 1.5% of GDP; this year it will be around 2% and around 2030 it will be at 3%.
Hopefully the frigates they purchase will be fully fitted with whatever missiles and guns are best meeting the needs of the RNoN. This is not the time to save money, especially when you are disgustingly rich. The "Oil Fund" is currently slightly above 17,200 billion NOK (1,630 Billion USD) and growing. How much would it be for five Type 26 off-the-shelf?